I don't see any problem. Your system load is 0.33, which is more than fine. On quad core it can go up to 4.00 without any problems and you can still have everything working fine up to 8.00-10.00 range. If you have many visitors it is normal that CPU and RAM is used.

What you fail to mention is whether there is any visible slowdown while you use the website? If there isn't any, then there is nothing you should worry about.